Evaluation of the Efficacy of a Novel Dermatotomy Device for Central Venous Cannulation.

OBJECTIVE: To test the effectiveness of a novel wire-guided scalpel (Guideblade) to create a precise dermatotomy incision for central venous catheter (CVC) insertion. DESIGN: Prospective, nonrandomized interventional study. SETTING: Stanford University, single-center teaching hospital. PARTICIPANTS: Cardiac and vascular surgical patients (n = 100) with planned CVC insertion for operation. INTERVENTIONS: A wire-guided scalpel was used during CVC insertion. RESULTS: A total of 188 CVCs were performed successfully with a wire-guided scalpel without the need for additional equipment in 100 patients, and 94% of CVCs were accomplished with only a single dermatotomy attempt. "No bleeding" or "minimal bleeding" at the insertion site was observed in 90% of patients 30 minutes after insertion and 80.7% at the conclusion of surgery. CONCLUSION: The wire-guided scalpel was effective in performing dermatotomy for CVC with a 100% success rate and a very high first-attempt rate. The wire-guided scalpel may decrease bleeding at the CVC insertion site.

The Penn Classification Predicts Hospital Mortality in Acute Stanford Type A and Type B Aortic Dissections.

OBJECTIVES: Mortality in acute aortic dissection varies depending on anatomic location, extent, and associated complications. The Stanford classification guides surgical versus medical management. The Penn classification stratifies mortality risk in patients with Stanford type A aortic dissections undergoing surgery. The objective of the present study was to determine whether the Penn classification can predict hospital mortality in patients with acute Stanford type A and type B aortic dissections undergoing surgical or medical management. DESIGN: Retrospective, observational study. SETTING: Tertiary care, university hospital. PARTICIPANTS: Patients with acute aortic dissection between January 2008 and December 2017. INTERVENTIONS: Examination of hospital mortality after surgical or medical management. MEASUREMENTS AND MAIN RESULTS: Three hundred fifty-two patients had confirmed dissections (186 type A, 166 type B). The overall mortality was 18.8% for type A and 13.3% for type B. Penn class A patients with type A or type B dissections undergoing surgical repair had the lowest mortality (both 3.1%). Penn class B, C, or B+C patients with type A dissections and Penn class B+C patients with type B dissections undergoing medical management had the greatest incidence of mortality (50.0%-57.1%). All others had intermediate mortality (6.7%-39.3%). Logistic regression analysis demonstrated that Penn class B, C, and B+C patients had a greater odds of mortality and predicted mortality than did Penn class A patients. CONCLUSIONS: The Penn classification predicts hospital mortality in patients with acute Stanford type A or type B aortic dissections undergoing surgical or medical management. Early endovascular repair may confer lower risk of mortality in patients with type B dissections presenting without ischemia.

The "Ice Age" in Cardiac Surgery: Evolution of the "Siberian" Method of Brain Protection During Deep Hypothermic Perfusionless Circulatory Arrest.

Deep hypothermic perfusionless circulatory arrest was the first practical neuroprotective technique used for open-heart surgery. It was refined at the Novosibirsk Medical Research Center in Siberia and was actively used from the mid-1950s until 2001.This review describes the development of this technique and its contribution to our understanding of the dynamic changes in human physiology during induced hypothermia for circulatory arrest without extracorporeal perfusion. Deep hypothermic perfusionless circulatory arrest was an important stepping stone in the development of modern approaches in neuroprotection and monitoring during cardiac surgery.

Keratolimbal allograft.

PURPOSE OF REVIEW: Keratolimbal allograft (KLAL) transplants limbal tissue attached to a corneoscleral carrier from a cadaveric donor to deliver a large number of stem cells to the recipient. The present article will provide a review of KLAL focusing on the recent literature. RECENT FINDINGS: Recent findings pertain to tissue selection, immunosuppression and adverse event profiles, and postoperative complications (particularly related to immunologic rejection). SUMMARY: KLAL permits the treatment of limbal stem cell deficiency eyes when there is no available living-related or autograft tissue with minimal risk of irreversible toxicity from modern systemic immunosuppression. The prevention of immunologic graft rejection with the use of systemic immunosuppression after KLAL is critical and may require extending systemic immunosuppression treatment longer than previously thought. With vigilant postoperative management, KLAL can allow successful treatment of the most severely diseased eyes.

Protocol for prevention of spinal cord ischemia after thoracoabdominal aortic surgery.

OBJECTIVE: This manuscript was written to present a systemic protocol for the prevention, early detection, and treatment of spinal cord ischemia following open and endovascular thoracoabdominal aortic operations. METHODS: This protocol was a collaborative effort between surgeons, anesthesiologists and intensivists. It was implemented at our institution in November 2007. Nurses are trained to prevent, rapidly detect and ultimately aid in the treatment of spinal cord ischemia. RESULTS: Implementation of this protocol has aided in prevention, detection and treatment of spinal cord ischemia in patients after open and endovascular thoracoabdominal aortic operations. CONCLUSION: Standardized care and reliance on trained nursing staff to monitor for symptoms following thoracoabdominal aortic operations are safe and aid in the rapid detection, treatment and reversal of spinal cord ischemia.

Longitudinal optical density analysis of subretinal fluid after surgical repair of rhegmatogenous retinal detachment.

PURPOSE: To investigate optical coherence tomography-derived reflectivity and optical density (OD) characteristics of persistent subretinal fluid (SRF) in eyes after surgical repair of macula-off rhegmatogenous retinal detachment. METHODS: Retrospective case series of nine eyes with macula-off rhegmatogenous retinal detachment that underwent surgical repair with either scleral buckling or vitrectomy with or without scleral buckling. Major inclusion criteria included 1) availability of high-quality optical coherence tomography scans at 2 or more time points, and 2) sufficient SRF for optical coherence tomography sampling without including tissue edges. Demographic, clinical, and optical coherence tomography imaging data were collected on all eyes. Optical density and SRF height measurements were obtained using a manual image segmentation method with ImageJ. Optical density measurements were standardized by conversion to optical density ratios to facilitate comparison between different visits and eyes. Correlations were assessed for significance through both univariate and multivariate regression analyses. RESULTS: Optical density ratio measurements increased with time after surgery, and this was statistically significant (P = 0.001, R = 0.331). Subretinal fluid height measurements decreased in all eyes. There was a significant correlation between optical density ratios and log of SRF height (P ≤ 0.001, R = 0.485). In multivariate analysis, neither optical density ratios nor SRF height was a statistically significant predictor of visual acuity. CONCLUSION: Changes in optical density ratios of the residual SRF after retinal detachment repair may be representative of changes in the SRF composition over time. This is in agreement with previous biochemical studies and may serve as a noninvasive method of assessing SRF content in vivo.

Severity and Duration of Metabolic Acidosis After Deep Hypothermic Circulatory Arrest for Thoracic Aortic Surgery.

OBJECTIVE: To determine the severity, duration, and contributing factors for metabolic acidosis after deep hypothermic circulatory arrest (DHCA). DESIGN: Retrospective observational study. SETTING: University hospital. PATIENTS: Eighty-seven consecutive patients undergoing elective thoracic aortic surgery with DHCA. INTERVENTIONS: Regression analysis was used to test for relationships between the severity of metabolic acidosis and clinical and laboratory variables. MEASUREMENTS AND MAIN RESULTS: Minimum pH averaged 7.27±0.06, with 76 (87%) having a pH<7.35; 55 (63%), a pH<7.30; and 7 (8%), a pH<7.20. The mean duration of metabolic acidosis was 7.9±5.0 hours (range: 0.0 - 26.8), and time to minimum pH after DHCA was 4.3±2.0 hours (1.0 - 10.0 hours). Hyperchloremia contributed to metabolic acidosis in 89% of patients. The severity of metabolic acidosis correlated with maximum lactate (p<0.0001) and hospital length of stay (LOS) (r = 0.22, p<0.05), but not with DHCA time, DHCA temperature, duration of vasoactive infusions, or ICU LOS. Patient BMI was the sole preoperative predictor of the severity of postoperative metabolic acidosis. LIMITATIONS: This retrospective analysis involved short-term clinical outcomes related to pH severity and duration, which indirectly may have included the impact of sodium bicarbonate administration. CONCLUSIONS: Metabolic acidosis was common and severe after DHCA and was attributed to both lactic and hyperchloremic acidosis. DHCA duration and temperature had little impact on the severity of metabolic acidosis. The severity of metabolic acidosis was best predicted by the BMI and had minimal effects on short-term outcomes. Preventing hyperchloremic acidosis has the potential to decrease the severity of metabolic acidosis after DHCA.

Reversible spinal cord ischemia as a complication of acute aortic intramural hematoma.

Aortic intramural hematoma is a variant of acute aortic dissection characterized by localized hemorrhage into the aortic media causing a separation of the intimal and adventitial layers of the aorta. Malperfusion represents an unusual presenting sign of acute intramural hematoma. Herein, we describe the case of a patient with an acute Type A IMH who developed reversible ischemic spinal cord syndrome after presenting with paraplegia as a consequence of malperfusion. A decision was made to delay operative repair and, instead, emergently apply medical interventions to increase spinal cord perfusion pressure. Medical treatment was effective for the treatment of spinal cord ischemia and operative repair of the intramural hematoma was accomplished after complete recovery of neurologic function. This is the third case ever reported of an intramural hematoma presenting in the form of spinal cord ischemia.

Decellularized Descemet Membrane Anterior Keratoplasty With Allogeneic Simple Limbal Epithelial Transplantation for Partial Limbal Stem Cell Deficiency Following Partial Keratolimbal Allograft Failure.

PURPOSE: The purpose of this study was to describe the use of Descemet membrane anterior keratoplasty (DMAK) with modified allogeneic simple limbal epithelial transplantation to treat a case of partial limbal stem cell deficiency (LSCD) following keratolimbal allograft failure. METHODS: Case report. RESULTS: A 21-year-old woman with autoimmune polyglandular syndrome-related LSCD presented with pain and decreased vision. There was partial failure and recurrence of LSCD after a severe/acute keratolimbal allograft rejection that led to persistent epithelial defects refractory to conservative therapy. This was treated with a superficial keratectomy and placement of a DMAK. A modified allogeneic simple limbal epithelial transplantation was performed with an overlying amniotic membrane and temporary tarsorrhaphy. There was epithelialization of the corneal surface by 3 to 4 weeks with an improved ocular surface. Despite partial recurrence of late staining, the cornea has remained epithelized, vision has improved, and the patient has remained pain-free more than 1.5 years following the procedure. CONCLUSIONS: DMAK may be a long-term substrate to help improve and maintain epithelization of the cornea up to 1.5 years. DMAK may be a viable alternative to using amniotic membrane as a scaffold in allogeneic simple limbal epithelial transplantation for treatment of partial LSCD. While late epithelial staining recurred in our patient, DMAK appears to prevent recurrent epithelial defects and reduce ocular surface pain, conveying an improvement in quality of life in patients at high risk of rejection/failure.